Re: [Qemu-devel] [PATCH 03/31] target/s390x: Use unwind data for helper_nc

[Aurelien Jarno]

On 2017-05-23 10:33, Thomas Huth wrote:
> On 23.05.2017 05:02, Richard Henderson wrote:
> > Signed-off-by: Richard Henderson 
> > ---
> >  target/s390x/mem_helper.c | 18 +-
> >  target/s390x/translate.c  |  1 -
> >  2 files changed, 9 insertions(+), 10 deletions(-)

Reviewed-by: Aurelien Jarno 

-- 
Aurelien Jarno  GPG: 4096R/1DDD8C9B
aurel...@aurel32.net http://www.aurel32.net

Re: [Qemu-devel] [PATCH 03/31] target/s390x: Use unwind data for helper_nc

[Thomas Huth]

On 23.05.2017 05:02, Richard Henderson wrote:
> Signed-off-by: Richard Henderson 
> ---
>  target/s390x/mem_helper.c | 18 +-
>  target/s390x/translate.c  |  1 -
>  2 files changed, 9 insertions(+), 10 deletions(-)
> 
> diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
> index db80d53..1018fe0 100644
> --- a/target/s390x/mem_helper.c
> +++ b/target/s390x/mem_helper.c
> @@ -122,20 +122,20 @@ static void fast_memmove(CPUS390XState *env, uint64_t 
> dest, uint64_t src,
>  uint32_t HELPER(nc)(CPUS390XState *env, uint32_t l, uint64_t dest,
>  uint64_t src)
>  {
> -int i;
> -unsigned char x;
> -uint32_t cc = 0;
> +uintptr_t ra = GETPC();
> +uint8_t cc = 0;
> +uint32_t i;
>  
>  HELPER_LOG("%s l %d dest %" PRIx64 " src %" PRIx64 "\n",
> __func__, l, dest, src);
> +
>  for (i = 0; i <= l; i++) {
> -x = cpu_ldub_data(env, dest + i) & cpu_ldub_data(env, src + i);
> -if (x) {
> -cc = 1;
> -}
> -cpu_stb_data(env, dest + i, x);
> +uint8_t x = cpu_ldub_data_ra(env, dest + i, ra);
> +x &= cpu_ldub_data_ra(env, src + i, ra);

I'd maybe do the access to src first, before  the access to dest ...
though I did not find anything in the PoP that really indicates that
access exceptions for src would have a higher priority here... so it
likely does not really matter...

> +cc |= x;
> +cpu_stb_data_ra(env, dest + i, x, ra);
>  }
> -return cc;
> +return cc != 0;
>  }
>  
>  /* xor on array */
> diff --git a/target/s390x/translate.c b/target/s390x/translate.c
> index 3a72c38..6aa9c90 100644
> --- a/target/s390x/translate.c
> +++ b/target/s390x/translate.c
> @@ -3048,7 +3048,6 @@ static ExitStatus op_nabsf128(DisasContext *s, DisasOps 
> *o)
>  static ExitStatus op_nc(DisasContext *s, DisasOps *o)
>  {
>  TCGv_i32 l = tcg_const_i32(get_field(s->fields, l1));
> -potential_page_fault(s);
>  gen_helper_nc(cc_op, cpu_env, l, o->addr1, o->in2);
>  tcg_temp_free_i32(l);
>  set_cc_static(s);
> 

Reviewed-by: Thomas Huth 

[Qemu-devel] [PATCH 03/31] target/s390x: Use unwind data for helper_nc

[Richard Henderson]

Signed-off-by: Richard Henderson 
---
 target/s390x/mem_helper.c | 18 +-
 target/s390x/translate.c  |  1 -
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
index db80d53..1018fe0 100644
--- a/target/s390x/mem_helper.c
+++ b/target/s390x/mem_helper.c
@@ -122,20 +122,20 @@ static void fast_memmove(CPUS390XState *env, uint64_t 
dest, uint64_t src,
 uint32_t HELPER(nc)(CPUS390XState *env, uint32_t l, uint64_t dest,
 uint64_t src)
 {
-int i;
-unsigned char x;
-uint32_t cc = 0;
+uintptr_t ra = GETPC();
+uint8_t cc = 0;
+uint32_t i;
 
 HELPER_LOG("%s l %d dest %" PRIx64 " src %" PRIx64 "\n",
__func__, l, dest, src);
+
 for (i = 0; i <= l; i++) {
-x = cpu_ldub_data(env, dest + i) & cpu_ldub_data(env, src + i);
-if (x) {
-cc = 1;
-}
-cpu_stb_data(env, dest + i, x);
+uint8_t x = cpu_ldub_data_ra(env, dest + i, ra);
+x &= cpu_ldub_data_ra(env, src + i, ra);
+cc |= x;
+cpu_stb_data_ra(env, dest + i, x, ra);
 }
-return cc;
+return cc != 0;
 }
 
 /* xor on array */
diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index 3a72c38..6aa9c90 100644
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -3048,7 +3048,6 @@ static ExitStatus op_nabsf128(DisasContext *s, DisasOps 
*o)
 static ExitStatus op_nc(DisasContext *s, DisasOps *o)
 {
 TCGv_i32 l = tcg_const_i32(get_field(s->fields, l1));
-potential_page_fault(s);
 gen_helper_nc(cc_op, cpu_env, l, o->addr1, o->in2);
 tcg_temp_free_i32(l);
 set_cc_static(s);
-- 
2.9.4